Factors Affecting the Accuracy of Eyewitness Testimony: Anxiety (AQA A-Level Psychology): Revision Notes
Factors Affecting the Accuracy of Eyewitness Testimony: Anxiety
What is anxiety?
Anxiety refers to an unpleasant emotional state involving heightened arousal that can significantly influence how we remember events we have witnessed. This psychological factor has become a central focus in eyewitness testimony research because real-life crimes and traumatic incidents often create high levels of anxiety in witnesses, potentially affecting the reliability of their accounts.
A major critique of eyewitness testimony research is that many studies rely on artificial laboratory scenarios with little emotional impact on participants. However, real-world events like violent crimes typically involve intense anxiety that can dramatically alter how witnesses process and recall information.
Researchers have identified that anxiety may cause witnesses to focus attention on certain aspects of an event while missing other important details.
The Yerkes-Dodson inverted-U hypothesis
Deffenbacher (1983) applied the inverted-U hypothesis (originally developed to describe the relationship between arousal and performance) to explain how anxiety levels influence the accuracy of eyewitness recall. According to this theory, moderate levels of anxiety can actually enhance memory performance by improving attention and detail processing.
The hypothesis suggests there is an optimal level of anxiety that produces the best recall accuracy. Below this point, witnesses may not be sufficiently alert to notice important details. However, once anxiety exceeds the optimal level, memory performance begins to decline as the heightened emotional state becomes counterproductive.
The Inverted-U Relationship
The relationship forms an inverted-U shaped curve with three key stages:
- Low anxiety: Poor performance due to insufficient alertness
- Moderate anxiety: Optimal performance with enhanced attention and accuracy
- High anxiety: Declining performance as stress overwhelms cognitive processes
Research findings have been mixed regarding whether this relationship holds true in practice, making it difficult to draw firm conclusions about the hypothesis.
Repression theory
Repression offers an alternative explanation for how anxiety affects eyewitness testimony. Freud (1894) proposed that anxiety can hinder memory recall because forgetting serves as a protective mechanism. According to this theory, our minds may unconsciously block access to traumatic or distressing memories to shield us from the emotional pain they would cause.
When witnesses experience high anxiety during traumatic events, repression theory suggests they may struggle to retrieve accurate memories later. This occurs because the mind prioritises emotional protection over factual accuracy, leading to incomplete or distorted recollections of anxiety-provoking situations.
Research evidence
The weapons effect
Research Study: The Weapons Effect
Loftus et al. (1987) demonstrated the weapons effect, showing that when witnesses observe someone carrying a weapon, they tend to focus their attention on the weapon rather than the person's face.
Key Finding: This anxiety-driven attention shift negatively impacts their ability to recall facial details and other identifying features of armed suspects.
Significance: The findings support the idea that anxiety can divert attention away from crucial aspects of criminal events.
Meta-analysis findings
Deffenbacher (1983) conducted a comprehensive meta-analysis examining 21 studies on anxiety and eyewitness testimony accuracy. The analysis revealed that heightened anxiety generally reduced the reliability of witness memories, supporting the notion that anxiety diverts attention from important situational details.
However, Deffenbacher (2004) later reviewed his earlier conclusions and found them overly simplistic. His updated meta-analysis of 63 studies discovered that eyewitness performance actually increased gradually with rising anxiety levels until reaching extremely high anxiety, after which there was a dramatic performance decline. This pattern supports a modified version of the inverted-U hypothesis known as catastrophe theory.
Real-world studies
Real-World Study: Bank Robbery Witnesses
Christianson and Hubinette (1993) studied witnesses to actual bank robberies, finding contradictory evidence suggesting that increased emotional arousal led to improvements in recall accuracy rather than impairments. This challenges the assumption that anxiety consistently harms eyewitness testimony.
Clinical Study: Health Clinic Participants
Peters (1988) examined people attending a health clinic for injections, where participants met a nurse who administered the injection and a researcher present for different periods.
Results: Later recognition was easier for the nurse than the researcher, suggesting heightened anxiety due to the injection procedure actually enhanced memory accuracy.
Laboratory research
Laboratory Study: Simulated Anxiety Conditions
Ginet and Verkampt (2007) created moderate anxiety in laboratory participants by falsely telling them that electrodes would deliver electric shocks during a traffic accident video viewing.
Results: Participants with this anxiety-inducing expectation showed superior recall of minor details compared to those told the electrodes were purely for recording purposes, suggesting moderate anxiety can enhance eyewitness testimony accuracy.
Oue et al. (2001) found that participants who viewed emotionally disturbing events recalled fewer details from the periphery of scenes compared to those witnessing emotionally neutral events, indicating anxiety may narrow the focus of attention during encoding.
Evaluation
Laboratory versus real-world validity
Much anxiety and eyewitness testimony research relies on laboratory studies, raising questions about whether findings apply to genuine crime situations.
Critical Real-World Evidence
Yuille and Cutshall (1986) investigated anxiety levels and recall accuracy among thirteen witnesses to a fatal shooting in Vancouver, Canada. Contrary to laboratory predictions, witnesses with higher anxiety levels demonstrated less accurate recall than those with lower anxiety, while witnesses with extremely high anxiety showed surprisingly accurate recall.
This challenges the inverted-U hypothesis since those with peak anxiety should have exhibited poor recall according to the theory.
Ethical considerations
Ethical Limitations in Research
Studies examining anxiety and eyewitness testimony present inherent ethical challenges because creating genuine anxiety states in participants could cause psychological harm. This limitation restricts researchers' ability to create truly realistic anxiety-inducing scenarios in controlled settings.
Individual differences and mediating factors
Deffenbacher (2004) noted that eyewitness testimony accuracy may be influenced by various mediating factors beyond anxiety levels. Age differences affect how individuals respond to anxiety-producing situations, and personality characteristics likely play important roles in determining how anxiety impacts memory processes. These individual differences suggest that anxiety's effects on eyewitness testimony may vary considerably between different people and situations.
Mixed research findings
The research presents contradictory evidence regarding anxiety's impact on eyewitness accuracy. While some studies support the weapons effect and show anxiety impairing memory, others demonstrate improved recall under high-anxiety conditions.
Koehler et al. (2002) found participants recalled stressful words less accurately than non-stressful words, supporting repression theory. However, Hadley and MacKay (2006) discovered stressful words were actually better remembered due to their memorable nature, suggesting repression may occur only in specific instances.
Key Points to Remember:
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Anxiety is an unpleasant emotional state that can significantly affect how witnesses remember events they have observed
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The Yerkes-Dodson inverted-U hypothesis suggests moderate anxiety enhances memory performance up to an optimal point, after which further increases cause memory decline
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The weapons effect demonstrates how anxiety can cause witnesses to focus on threatening objects rather than important identifying details like faces
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Research findings are mixed - some studies show anxiety impairs eyewitness testimony while others demonstrate improved recall under high-anxiety conditions
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Real-world validity remains questionable as most research relies on laboratory studies that may not reflect the true emotional impact of witnessing actual crimes